ACTION OF METRAZOL PENTAMETHYLENETETRAZOL) ON THE HYPOTHALAMUS OF THE CAT

The results of a series of experiments designed to investigate the effect of pentamethylenetetrazol (metrazol), when injected either intravenously or directly into the diencephalon, on the functions of the hypothalamus and on its responses to faradic stimulation in anesthetized and in recovery preparations are presented.

Abstract

It is my purpose in this report to present the results of a series of experiments designed to investigate the effect of pentamethylenetetrazol (metrazol), when injected either intravenously or directly into the diencephalon, on the functions of the hypothalamus and on its responses to faradic stimulation in anesthetized and in recovery preparations. METHODS The experimental methods employed in these studies have been described in detail elsewhere;1in brief, they were as follows: Acute Preparations (8 animals). —A cat was placed under light ether anesthesia and was prepared for kymographic recording of the respiration and the blood pressure. An insulated bipolar needle electrode was then inserted into the hypothalamus by the Horsley-Clarke stereotaxic technic, rendering possible observations of the muscular and vegetative reactions to faradic stimulation of the hypothalamus and the changes in these reactions produced by the intravenous or intradiencephalic injection of a solution of metrazol. Recovery Preparations (7